Environmental Control Automation~
AoT's env_coordinator is a 3-layer control system that automatically manages greenhouse environment parameters — VPD, CO₂, temperature, and humidity.
VPD (Vapor Pressure Deficit)~
VPD is the key metric determining plant transpiration and water uptake.
| Range | Status | Recommended crop stage |
|---|---|---|
| < 0.4 kPa | Too low — mold risk | — |
| 0.4–0.8 kPa | Optimal | Germination / early transplant |
| 0.8–1.2 kPa | Optimal | Vegetative growth |
| 1.2–1.8 kPa | Optimal | Flowering / fruiting |
| > 1.8 kPa | Too high — water stress | — |
env_coordinator Control Layers~
L1 — EnvTarget (setpoint)~
Reads VPD / CO₂ targets from a Method curve or fixed values.
- Method: Time-based target curve by crop stage (seeding to harvest)
- Fixed value: Use a constant setpoint for simple operation
L2 — SituationReport (evaluation)~
Evaluates current deviation, limiting factors, and trend.
| Evaluation item | Description |
|---|---|
| Deviation | current value - target |
| Limiting factor | Which of temperature/humidity/CO₂ is preventing VPD from reaching target |
| Trend | Whether the value is moving toward the target |
L3 — Coordinator (actuator command)~
Applies PI control + slew rate limiting + anti-windup to command actuators.
e(t) = setpoint - measurement
u(t) = Kp × e(t) + Ki × ∫e dt
slew: |Δu| ≤ slew_rate_per_cycle
output → heater / vent fan / humidifier / CO₂ supply
Function Configuration~
Navigate to Functions → env_coordinator in the AoT UI.
Key settings~
| Field | Description |
|---|---|
| Input (temperature) | Connect indoor temperature sensor |
| Input (humidity) | Connect indoor humidity sensor |
| VPD Method | VPD target curve by crop stage |
| CO₂ Method | CO₂ target curve |
| Output (heater) | Connect heating actuator |
| Output (vent fan) | Connect ventilation actuator |
| Output (humidifier) | Connect humidifier actuator |
| Output (CO₂) | Connect CO₂ supply actuator |
Methods (Setpoint Curves)~
A Method defines how a setpoint changes over time.
Example crop stage schedule (tomato):
| Day | VPD target | CO₂ target |
|---|---|---|
| Seeding–Day 7 | 0.6 kPa | 800 ppm |
| Day 8–21 | 0.8 kPa | 900 ppm |
| Day 22–42 | 1.0 kPa | 1000 ppm |
| Day 43+ | 1.3 kPa | 1000 ppm |
Methods prefixed with SEED: are seed presets and are read-only. Duplicate a preset before editing.
Safety Gates~
Multiple safety mechanisms are applied to control actions.
| Safety gate | Description |
|---|---|
| High-temp cutoff | Forces heating OFF if indoor temp > threshold |
| CO₂ ceiling | Forces CO₂ supply OFF if CO₂ > 1500 ppm |
| Sensor failure | Enters safe mode if sensor value stays stale |
| Manual Lock | AI or user can pause automatic control |
AI Integration~
The AI agent uses analyze_control_performance to diagnose control quality.
vpd_rmse → VPD tracking error (lower is better)
oscillation_index → Control oscillation index (lower is more stable)
assessment → "good" / "moderate" / "poor"
Based on diagnostics, suggest_setpoint_adjustment proposes a target adjustment. After user approval, set_vpd_target applies it.